Retaining structure for removably mounting a surfboard fin

ABSTRACT

A retaining structure for a surfboard fin includes a mounting base secured in the undersurface of a surfboard, a fin member and two blocks. The mounting base has a receptacle and two holding portions. The fin member has a connecting section to be embedded in the receptacle of the mounting base and a body section extending from the connecting section. The body section of the fin member protrudes outside the undersurface of the surfboard and has front and rear ends inclined outwardly. Each block is detachably mounted on the respective holding portion of the mounting base and defines a recess in a side according to the slope of the respective inclined end of the body section so that the inclined ends of the body section can be fitted in the recesses of the blocks and suppressed by the blocks and thereby be secured onto the mounting base.

BACKGROUND OF INVENTION

1. Field of Invention

This invention relates to a fin construction to be mounted on the underneath of a surfboard and more particularly to a fin retaining structure for removably mounting a surfboard fin.

2. Related Prior Art

Retaining structures to mount fins onto the underneath of surfboards are known in the art. Such structures are typically configured to create a rigid connection between the fin and the body as secure as possible. Such retaining structures are herein defined generally as designed to permit the removal of fin member without the extensive use of tools from the surfboard. Such retaining structures for the surfboard fin generally provide some facilitation in the assembly of fin members and permit the ordinary user to rapidly change a fin member.

One such structure is described in U.S. Pat. No. 3,516,099 to Thomas et al. and is directed to a mounting structure for tightly securing a skeg or fin to a surfboard. The mounting structure includes a channeled mounting box bonded in the rear ward portion of a surfboard. The sidewalls of the box are shaped with complementary tapering. The base of the fin is directly secured in the box by screws, which upon tightening, snugly wedge the side walls together to prevent wobbling or other relative movement between fin and box that could interfere with surfing operations.

Another mechanism for fin retaining structure is described in U.S. Pat. No. 5,030,151 to Christopher J. Beacham and relates to fins for watercrafts. These fins have an apertured, basal flange. Each fin is affixable, in a variety of positions, to the underside of the watercraft via fixing means extending through the apertures in the flange and into the fabric of the watercraft. Although the fin may be affixed to the underside of the watercraft easily via the screws, the apertured flange affects the appearance in a negative way.

A heretofore unmet need exists for a fin retaining structure in which fin members can be easily and firmly assembled to the board, with attractive appearance, and are to be removed therefrom easily as well.

SUMMARY OF INVENTION

Broadly stated, the present invention is directed to a retaining structure for removably mounting a surfboard fin. The retaining structure includes a mounting base, a fin member, and two suppressing mechanisms. The mounting base is firmly secured within a cavity in the undersurface of a surfboard. Moreover, the mounting base has a receptacle and two holding portions adjacent to opposite ends of the receptacle. The fin member has a connecting section and a body section extending from the connecting section. The connecting section is to be embedded in the receptacle of the mounting base. The body section protrudes outside the undersurface of the surfboard and has its front and rear ends inclined outwardly. In particular, each of the two suppressing mechanisms is detachably mounted on the respective holding portion of the mounting base and includes a block. Specifically, one of the blocks defines a recess in a side thereof according to the slope of the inclined front end of the body section of the fin member while the other block defines a recess in a side thereof corresponding to the slope of the inclined rear end of the body section in such a way that the inclined front and rear ends of the body section can be fitted in the recesses of the blocks and suppressed by the blocks and thereby be secured onto the mounting base.

The present invention and the advantages thereof will become more apparent upon consideration of the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

The invention is illustrated by the accompanying drawings in which corresponding parts are identified by the same numerals and in which:

FIG. 1 is a perspective view of a fin retaining structure in accordance with a first embodiment of the invention;

FIG. 2 is an exploded view of the fin retaining structure of FIG. 1;

FIG. 3 is an enlarged view of a block of the fin retaining structure of FIG. 2;

FIG. 4 is a cross-sectional view of the fin retaining structure of FIG. 1 together with a surfboard to which the fin retaining structure is attached;

FIG. 5 is a partly enlarged side view of the fin retaining structure of FIG. 4;

FIG. 6 is a partly enlarged top view of the fin retaining structure of FIG. 4;

FIG. 7 is a perspective view of a fin retaining structure, along with the surfboard, in accordance with a second embodiment of the invention; and

FIG. 8 is a perspective view of a fin retaining structure, along with the surfboard, in accordance with a third embodiment of the invention;

DETAILED DESCRIPTION OF EMBODIMENTS

Referring now to the FIG. 1, a fin retaining structure is shown having a mounting base 1, a fin member 2 and two suppressing mechanisms 300. The mounting base 1 is to be firmly secured within a cavity in the undersurface of a surfboard, as shown in FIG. 4. Each of the suppressing mechanisms 300 includes a block 3 and a fixing part 4. The fin member 2 is attached to the mounting base 1 with the help of the two suppressing mechanisms 300.

As shown in FIG. 2, the mounting base 1 includes a base portion 11, a patch plate 12 and a receptacle (to be described hereinafter). The base portion 11 is fitted in a main upper portion of the cavity (see FIG. 4) and has a channel 13 and two holding portions 14 adjacent to opposite ends of the channel 13. Each of the holding portions 14 of the base portion 11 defines a fixing hole 15, such as a threaded hole, for reception of the fixing part 4. In addition, a plurality of ribs 16 is arranged around the base portion 11 to provide relatively more outer surface. The patch plate 12 is a separate structure that is fitted into a lower portion of the cavity in the undersurface of the surfboard 10 to allow the bottom of mounting base 1 flush with the undersurface of the surfboard 8. Further, the patch plate 12 defines an opening 13 a therethrough. In fact, the stacked patch plate 12 and the base portion 11 co-define the receptacle of the mounting base 1, namely the opening 13 a plus the channel 13, in order to receive a connecting section 22 of the fin member 2.

As shown in FIG. 4, the base portion 11 of the mounting base 1 is embedded in a foam core 81 of the surfboard 8. In order to attach the base portion 11 onto the foam core 81 securely, a method to fulfill that purpose is provided herein. First, coat the base portion 11 with hot-melt adhesive around. Next, place the coated base portion 11 in to a mold (not shown) in which a shaped cavity is defined according to the surfboard. Then, fill the mold with some foam materials, such as PE, PS or PS pre-foam beads. After that, heat the mold to form the shaped foam core along with the base portion 11 mounted thereon. It is noted that the hot-melt adhesive, under heat treatment, will disperse outwardly and randomly in such a way that the dispersed adhesive will then tightly grasp the heated foaming materials and the base portion 11 together once the temperature is brought low. For this reason, the base portion 11 of the mounting base 1 can be tightly bonded to the foam core 81. It should be understood that the ribs 16 around the base portion 11 further enlarge the contact surface therebetween and greatly strengthen the bonding of the base portion 11 to the foam core 81. As can be seen in FIG. 4, the base portion 11 of the mounting base 1 is secured in the cavity with its bottom surface flush with the undersurface of the foam core 81 of the surfboard 8. In particular, the channel 13 and the holding portion 14 of the base portion 11 are exactly exposed on a certain area of the undersurface of the foam core 81.

After the base portion 11 is firmly bonded to the foam core 81, a bottom skin 82 is then laminated onto the undersurface of the foam core 81 as well as the exposed channel 13 and holding portion 14 of base portion 11. Furthermore, a top skin 83 is laminated onto top and edges of the foam core 81.

It should be understood that the top or bottom skin 82 or 83 may be formed of a single or multi-layer material. For example, the bottom skin 82 is preferably made by a combination of a smooth plastic board and a PE foam layer. Likewise, the top skin 83 may be formed in one piece or be made up by pieces. The preferable combination for the top skin 83 is a PE foam material along with a plastic patterned laminate covered thereon.

When the top and bottom skins 83, 82 are both bonded onto the exterior surfaces of the foam core 81, a specific segment of the bottom skin 82 by which the base portion 11 is covered is then cut away in order to expose the channel 13 and the holding portions 14 of the base portion 11 on that certain area again. The left space where the segment is cut away, namely the lower portion of the cavity in the undersurface of the surfboard, is then be filled up with the patch plate 12.

Referring to FIGS. 2 and 4, in order to create secure connection between the patch plate 12 and the base portion 11, a plurality of upright bolts 18 extends from top of the patch plate 12 and a plurality of holes 17 is defined in the undersurface of the base portion 11 for reception of the bolts 18. In this way, the patch plate 12 can be temporarily engaged with the base portion 11 and later be permanently bonded to the base portion 11 in any known manner such as by adhesives or high-frequency welding or any other suitable known means.

As mentioned above, the patch plate 21 has the opening 13 a in which the channel 13 and the holding portions 14 of the base portion 11 are exposed when the patch plate 12 and the base portion 11 are coupled. Additionally, the patch plate 12 is shaped to perfectly fit the left space where the cut-away segment left behind. The patch plate 12 may be further trimmed as needed in order to have its bottom surface flush with the undersurface of the bottom skin 82 of the surfboard 8. It should be noted that, in other examples, the patch plate 12 may be left out and excluded from the surfboard 8 as one's wish.

According to the aforementioned method, it is advantageous to be able to assemble the surfboard 8, the mounting base 1 and the fin member 2 all together under relatively lower cost without decreasing the quality.

Referring back to FIG. 2, the fin member 2 includes the connecting section 22 and a body section 21. The body section 21 extends from the bottom of the connecting section 22 and protrudes outside the undersurface of the surfboard 8. In construction, the body section 21 and the connecting section 22 are formed, but not limited to be, in one piece.

As shown in FIGS. 2 and 3, the body section 21 of the fin member 2 has front and rear ends 211, 212 inclined outwardly. One of the blocks defines a recess in a side thereof according to the slope or shape of the inclined front rear 211 of the body section 21 while the other block defines a recess in a side thereof according to the slope of the inclined rear 212 end of the body section 21.

Each of the two suppressing mechanisms 300 is detachably mounted on the respective holding portion 14 of base portion 11 of the mounting base 1. Specifically, each of the blocks 3 defines a through hole 31 from top to bottom to receive the respective fixing part 4. When the fin member 2 is to be used for surfing, it is quite easy for the surfer to mount the fin member 2 onto the surfboard 8, as shown in FIG. 4. All you have to do is to insert the connecting section 22 of the fin member 2 into the receptacle of the mounting base 1, and then to have the fixing parts 4 pass through the holes 31 of the blocks and be locked to the fixing holes 15 of the mounting base 1. For convenience sake, the fixing parts 4 are screws while the fixing holes 15 are threaded holes correspondingly. That is, the blocks 3 and the fixing parts 4 are threadably engaged with the base portion 11 of the mounting base 1. When the fixing parts 4 are screwed into the fixing holes 15, the blocks 3 will tightly press the fin member 2 onto the mounting base 1. It follows that when the fixing parts 4 are screwed the blocks 3 to the holding portions 14 of the base portion 11, the inclined front and rear ends 211, 212 of the body section 21 can be fitted in the recesses 32 of the blocks 3 and suppressed by the blocks 3 and thereby be secured onto the mounting base 1, as shown in FIG. 4. FIG. 5 clearly shows that one block 3 abuts against a sidewall of the inclined front end 211. Preferably, the recesses 32 of the blocks 3 are generally dimensioned in accordance with the inclined front and rear ends 211, 212, as depicted in FIG. 6, in order to be perfectly tied in with the fin member 2. It is realized that using the blocks 3 suppressing the inclined front and rear ends 211, 212 of the fin member 2 enables the fin member 2 to be simple in shape and therefore be easy to be manufactured, which helps bring fin product cost down.

On the other hand, since the blocks 3 are releasably affixed to the undersurface of the surfboard 8, the fin member 2 may also be easily removed from the surfboard 8 to allow for easy of transport, inasmuch as the surfboard 8 with the fin member 2 removed could be safely stacked one on top of the other. In such cases, the fin member 2 can be easily removed off by simply screwing the fixing parts 4 off the holding portions 14. Removing the fin member 2 from the surfboard 8 helps to save great space and prevent the fin member from damage. In summary, the employment of the blocks 3 to suppress the fin members 2 enables the quick attachment or detachment of the fin member 2 to the surfboard 8.

FIG. 7 provides a cross-sectional view of a fin retaining structure, along with a surfboard 8, in a second embodiment. As can be seen from the drawing, the second embodiment is generally similar to the first embodiment, comprising a mounting base 1, a fin member 2, a first block 3 a, a second block 3 and a fixing part 4. The mounting base 1 is firmly secured within a cavity in the undersurface of the surfboard 8. The mounting base 1 has a receptacle and two holding portions 14. One of the holding portions 14 defines a fixing hole 15 therein for reception of the fixing part 4, such as a screw. The fin member 2 has a connecting section 22 embedded in the receptacle of the mounting base 1 and a body section 21 extending from the connecting section 22. The body section 21 protrudes outside the undersurface of the surfboard 8. In particular, the first block 3 a is integrated with the mounting base 1 and provided to suppress the rear end 212 of the body section 21 of the fin member 2. It should be noted that, in another example, the first block 3 a may be configured to suppress the front end 211 of the body section 21 rather than the rear end 212 as one's wish.

Similar to the suppressing mechanisms 300 of FIG. 2, the second block 3 defines a through hole 31 from top to bottom, and the fixing part 4 passes through the through hole 31 of the second block 3 and is screwed to the threaded fixing hole 15 of the holding portion 14. In this way, the fixing part 4 along with the second block 3 is releasably locked in the fixing hole 15 of the holding portion 14 in order to secure the second block 3 onto the holding portion 14 of the mounting base 1 and thereby enable the second block 3 to suppress the front end 211 of the body section 21 of the fin member 2.

As described above, it is realized that the second embodiment includes the unique first block 3 a which is integrated with the base portion 11 or the patch block 12 of the mounting base 1 into one piece. In construction, the first block 3 a together with the base portion 21 or the patch block 22 may be formed by plastics molding or the like. Alternatively, the first block 3 a may be formed in advance and then be bonded to the base portion 21 or the patch block 22 by adhesives or high-frequency welding. In this way, in operation, only the second block 3 and the fixing part 4 are needed to be handled for assembling. It should be noted that both the recesses 32 a of the block 3 a and the recess 32 of the block 3 are dimensioned in accordance to the inclined front and rear ends 211, 212 of the body section 21 of the fin member 2, as taught above for the first embodiment.

With reference to FIG. 8, a fin retaining structure, along with a surfboard, in accordance with a third embodiment of the invention is illustrated. As can be seen from the drawing, the third embodiment is generally similar to the first embodiment, comprising a mounting base 1, a fin member 2, two blocks 3 b and two fixing parts 4. The mounting base 1 is firmly secured within a cavity in the undersurface of the surfboard 8. Moreover, the mounting base 1 has a receptacle and two holding portions 14 adjacent to opposite ends of the receptacle. The fin member 2 has an unique connecting section 22 b embedded in the receptacle of the mounting base 1 and a body section 21 extending from the connecting section 22 b. As shown, the body section 21 protrudes outside the undersurface of the surfboard 8. The main difference between the first and third embodiments is that the connecting section 22 b has a width slightly greater than that of the body section 21 to such an extent that the front and rear ends 211 b, 212 b of the connecting section 22 b extends outside the front and rear ends of the body section 21 respectively.

Similar to the suppressing mechanism 300 of FIG. 2, each of the two blocks 3 b defines a through hole from top to bottom for reception of the two fixing parts 4. That is, the fixing parts 4 pass through the through holes of the blocks 3 b and then are screwed to the threaded fixing holes 15 of the holding portions 14. In this way, the fixing parts 4 together with the blocks 3 b are releasably locked in the fixing holes 15 in order to secure the blocks 3 b onto the holding portions 14 of the mounting base 1 and thereby enable the blocks 3 b to suppress the front and rear ends 211 b, 212 b of the connecting section 22 b of the fin member 2.

It should be noted that it is not necessary to define any recess in the blocks 3 b to receive the front and rear ends of the body section 21 of the fin member 2. In this embodiment, since the two ends of the body section 21 are not inclined (see FIG. 8), no side recess is defined in the blocks 3 b. However, in another example, recesses 32, may be further defined as needed. Furthermore, in another example, one of the blocks 3 b may be integrated with the mounting base 1 into one piece, as discussed in the second embodiment.

It will be appreciated that although a particular embodiment of the invention has been shown and described, modifications may be made. It is intended in the claims to cover such modifications which come within the spirit and scope of the invention. 

1. A retaining structure for removably mounting a surfboard fin comprising: a mounting base firmly secured within a cavity in the undersurface of a surfboard; the mounting base having a receptacle and two holding portions adjacent to opposite ends of the receptacle; a fin member having a connecting section to be embedded in the receptacle of the mounting base and a body section extending from the connecting section, the body section protruding outside the undersurface of the surfboard and having front and rear ends inclined outwardly; and two suppressing mechanisms each detachably mounted on the respective holding portion of the mounting base and each including a block, wherein one of the blocks defines a recess in a side thereof according to the slope of the inclined front end of the body section of the fin member while the other block defines a recess in a side thereof according to the slope of the inclined rear end of the body section in such a way that the inclined front and rear ends of the body section can be fitted in the recesses of the blocks and suppressed by the blocks and thereby be secured onto the mounting base.
 2. The retaining structure of claim 1 wherein each of the two holding portions of the mounting base defines a fixing hole therein; each of the suppressing mechanisms includes a block defining a through hole from top to bottom and a fixing part configured to pass through the through hole of the block and be releasably locked in the fixing hole in order to secure the block onto the respective holding portion of the mounting base and thereby enable the block to suppress the fin member.
 3. The retaining structure of claim 2 wherein the mounting base includes a base portion having the holding portions thereon and a patch plate shaped to fit for the base portion; the receptacle of the mounting base passes through the patch plate and into the base portion; and when the base portion is coupled with the patch plate, the receptacle and the holding portions are exposed in an opening of the patch plate.
 4. A retaining structure for removably mounting a surfboard fin comprising: a mounting base firmly secured within a cavity in the undersurface of a surfboard; the mounting base having a receptacle and a holding portion defining a fixing hole therein; a fin member having a connecting section to be embedded in the receptacle of the mounting base and a body section extending from the connecting section, the body section protruding outside the undersurface of the surfboard; a first block integrated with the mounting base and provided to suppress one end of the body section of the fin member; a second block defining a through hole from top to bottom; and a fixing part configured to pass through the through hole of the second block and be releasably locked in the fixing hole of the holding portion in order to secure the second block onto the holding portion and thereby enable the second block to suppress the other end of the body section of the fin member.
 5. The retaining structure of claim 4 wherein the two ends of the body section of the fin member are inclined outwardly and each of the first and second blocks defines a recess in a side thereof according to the slope of the respective inclined end of the body section of the fin member in such a way that one inclined end of the body section can be fitted in the recess of the first block and suppressed by the first block which is integrated with the mounting base while the other inclined end of the body section is fitted in the recess of the second block and is suppressed by the second block which is secured on the mounting base by the fixing part.
 6. The retaining structure of claim 5 wherein the fixing part is a screw and the fixing hole defined in the holding portion is threaded.
 7. A retaining structure for removably mounting a surfboard fin comprising: a mounting base firmly secured within a cavity in the undersurface of a surfboard; the mounting base having a receptacle and two holding portions adjacent to opposite ends of the receptacle; a fin member having a connecting section to be embedded in the receptacle of the mounting base and a body section extending from the connecting section, the body section protruding outside the undersurface of the surfboard, wherein the connecting section has a width slightly greater than the body section to such an extent that the front and rear ends of the connecting section extends outside the front and rear ends of the body section respectively; two blocks each defining a through hole from top to bottom; and two fixing parts configured to pass through the through holes of the blocks and be releasably locked in the fixing holes of the holding portions in order to secure the blocks onto the holding portions of the mounting base and thereby enable the blocks to suppress the front and rear ends of the connecting section of the fin member.
 8. The retaining structure of claim 7 wherein the fixing parts are screws and the fixing holes defined in the holding portions are threaded. 